Schapery s theory

There are gum rubbers which do not obey the relationship given by equation 6.27. One case is rubber exhibiting strain-hardening. The linearisation in this case is in terms of Schapery s theory, h = 0,h =, h2 = T(a), and a = 11 a. T(a) represents the extent of strain-hardening and must be determined from experimental measurements ... 

A phenomenological explanation has been given for equations 6.27-6.29 by this author [12] without reference to Schapery s theory. It is a rational analysis of the relationship between macroscopic deformation and the deformation in the segmental level of polymer chains. An increase of free volume resulting from deformation in the dynamic state is the explanation for the strain-time correspondence. 

R. A. Schapery, A Theory of Nonlinear Thermoviscoelasticity Based on Irreversible Thermodynamics Proc. 5th U. S. National Congress of Applied Mechanics, ASME, New York, 1966, pp. 511-530. 

A thermodynamically consistent theory for nonlinear viscoelasticity was first proposed by Schapery.(26) Jhe law can be derived from fundamental principles using the concepts of irreversible thermodynamics. A comprehensive review of the thermodynamics basis of Schap-ery s theory has been presented by Hiel et... 

Schapery [16, 17] has used the theory of the thermodynamics of irreversible processes to produce a model that may be viewed as a further extension of Leaderman s. Schapery continued Leaderman s technique of replacing the stress by a function of stress /(a) in the superposition integral, but also replaced time by a function of time, the reduced time ip. The material is assumed to be linear viscoelastic at small strains, with a creep compliance function of the form [17]... 

R. A. Schapery, Further Development of a Thermodynamic Constitutive Theory Stress Formulation, A S Report No. 69-2, Purdue University, W. Lafayette (Feb. 1969). 

In 1963 Nagdi and Murch published a paper entitled On the Mechanical Behavior of Viscoelastic-Plastic Solids just before Schapery first published his efforts on a thermodynamic approach to nonlinear viscoelasticity and prior to the development of early viscoplastity theories. Likely because both nonlinear viscoelasticity and/or viscoplasticity caught the attention of the technical community, Nagdi s work received little attention. However,... 

Schapery, R. A., "A Theory of Non-Linear Thermoviscoelasticity Based on Irreversible Thermodynamics," Proc. Fifth U.S. Nat. Cong, of Appl. Mech., ASME, 511-530 (1966). 

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